<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>52</ContextCount>
  <ElementCount>144</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>9</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>6</UnitCount>
  <MyReports>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>995100 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/dei/role/document/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>995300 - Document - Audit Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/dei/role/document/AuditInformation</Role>
      <ShortName>Audit Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>995301 - Statement - Consolidated Statements of Financial Condition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/ConsolidatedCashFlow</Role>
      <ShortName>Consolidated Statements of Financial Condition</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>995302 - Statement - Consolidated Statements of Financial Condition (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/ConsolidatedCashFlow_Parentheticals</Role>
      <ShortName>Consolidated Statements of Financial Condition (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>995303 - Statement - Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/ConsolidatedIncomeStatement</Role>
      <ShortName>Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>995304 - Statement - Consolidated Statements of Changes in Members' Capital</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/ShareholdersEquityType2or3</Role>
      <ShortName>Consolidated Statements of Changes in Members' Capital</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>995305 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/ConsolidatedCashFlow0</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>995306 - Disclosure - Organization and Business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/OrganizationandBusiness</Role>
      <ShortName>Organization and Business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>995307 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/SummaryofSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>995308 - Disclosure - Capital Accounts</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/CapitalAccounts</Role>
      <ShortName>Capital Accounts</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>995309 - Disclosure - Fees and Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/FeesandRelatedPartyTransactions</Role>
      <ShortName>Fees and Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>995310 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>995311 - Disclosure - Risk Factors</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/RiskFactors</Role>
      <ShortName>Risk Factors</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>995312 - Disclosure - Financial Highlights</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/FinancialHighlights</Role>
      <ShortName>Financial Highlights</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>995313 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure</Role>
      <ShortName>Cybersecurity Risk Management and Strategy Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>996000 - Disclosure - Accounting Policies, by Policy (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/AccountingPoliciesByPolicy</Role>
      <ShortName>Accounting Policies, by Policy (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/SummaryofSignificantAccountingPolicies</ParentRole>
      <Position>18</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>996001 - Disclosure - Fees and Related Party Transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/FeesandRelatedPartyTransactionsTables</Role>
      <ShortName>Fees and Related Party Transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/FeesandRelatedPartyTransactions</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>996002 - Disclosure - Financial Highlights (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/FinancialHighlightsTables</Role>
      <ShortName>Financial Highlights (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/FinancialHighlights</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>996003 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/SummaryofSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>996004 - Disclosure - Capital Accounts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/CapitalAccountsDetails</Role>
      <ShortName>Capital Accounts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/CapitalAccounts</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>996005 - Disclosure - Fees and Related Party Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/FeesandRelatedPartyTransactionsDetails</Role>
      <ShortName>Fees and Related Party Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/FeesandRelatedPartyTransactionsTables</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>996006 - Disclosure - Fees and Related Party Transactions - Sponsor Fees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/SponsorFeesTable</Role>
      <ShortName>Fees and Related Party Transactions - Sponsor Fees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>996007 - Disclosure - Financial Highlights - Operating Performance Calculation Per Unit (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/OperatingPerformanceCalculationPerUnitTable</Role>
      <ShortName>Financial Highlights - Operating Performance Calculation Per Unit (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>996008 - Disclosure - Financial Highlights - Ratios to Average Members' Capital and Total Return (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/RatiostoAverageMembersCapitalandTotalReturnTable</Role>
      <ShortName>Financial Highlights - Ratios to Average Members' Capital and Total Return (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="ef20060624_10k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>996009 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://grahamgaifb.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://grahamgaifb.com/role/SubsequentEvents</ParentRole>
      <Position>27</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-K" isDefinitelyFs="true" isUsgaap="true" original="ef20060624_10k.htm">ef20060624_10k.htm</File>
    <File>gaifb-20251231.xsd</File>
    <File>gaifb-20251231_cal.xml</File>
    <File>gaifb-20251231_def.xml</File>
    <File>gaifb-20251231_lab.xml</File>
    <File>gaifb-20251231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>image00001.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="215">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="16">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="35">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
